Dr. Punyamurtula Kishore has already been charged with running an elaborate scheme involving paying kickbacks to drug treatment programs that sent him work covered by MassHealth.

But authorities say that’s just the beginning for the founder of Preventive Medicine Associates, whose offices included clinics in Weymouth and Quincy, and the Brookline-based nonprofit National Library of Addictions.

Kishore, 61, was arrested Tuesday night at his home in Brookline and charged with one count of giving what the state calls “medical assistance bribes/kickback.” He pleaded innocent at his arraignment in Malden District Court on Tuesday and was ordered held on $150,000 cash bail.

Attorney General Martha Coakley’s office alleges that Kishore gave kickbacks to housing programs for recovering drug addicts that sent urine drug screening work to his labs for patients eligible for Medicaid benefits. Kishore was then reimbursed by Medicaid for the testing.

Coakley’s office said the alleged scheme involved about $500,000 in taxpayer money and lasted from 2006 to 2009.

At the arraignment, Assistant Attorney General Nancy Maroney said the investigation is ongoing and that more charges are coming.

“This is just the tip of the iceberg,” she said. “There are a bunch of indictments that are about to be handed down in this case.”

Kishore, who is from India and is a permanent resident of the United States but is not a citizen, was ordered to surrender his passport if he makes bail and meet with a probation officer weekly.

His attorney, Mark Berthiaume, said Kishore is not a flight risk and has been cooperating with authorities in their investigation.

“This man ... has shown no signs of fleeing the situation – just the opposite: dealing with it, attempting to address the Attorney General’s Office and repeatedly requesting an opportunity to meet and explain his side,” Berthiaume said during the arraignment.

The Patriot Ledger reported Wednesday that several of Kishore’s offices, including one on Coddington Street in Quincy, had closed recently. In a statement prepared by a spokesman, Kishore said Tuesday that he was forced to “re-evaluate the financial viability” of his offices “in light of new health care regulations and reimbursement policies.”

Kishore started the for-profit company in 1996 in Brighton.

It’s unclear exactly how many clinics are part of Preventive Medicine Associates. The company’s website lists 33 offices, including locations in Sandwich, Wareham and Quincy that had closed in recent months. The statement from the spokesman said he has 47 offices. A press release from the Attorney General’s Office puts the number at 29.

Several former employees said they hadn’t been paid for as long as seven weeks and that rumors began circulating earlier this week that the remaining offices would close for good Friday.